science

The risks to children in their everyday environments are numerous. But there are six groups of environmental health hazards that must be tackled as priority issues --- household water security, lack of hygiene and poor sanitation, air pollution, vector-borne diseases, chemical hazards, and unintentional injuries (accidents). These risks exacerbate the effects of economic underdevelopment and they cause the bulk of environment-related deaths and disease among children.

For most of these priority risks, security, stability, emergency preparedness and economic development are key to overcoming them. While experience shows that even in underdeveloped economies, these risks can be significantly reduced, experience also shows that, in higher income societies, the overall burden of environmental diseases in children decreases --- at the same time as the relative priorities change. Therefore, regions and countries will have to set their specific priorities to complement these global ones.

1. Household water security

Household water security covers the reliable availability of safe water in the home for all domestic purposes. Access to a reliable safe water supply is a human right as defined in the General Comment on the Right to Water and the Declaration on the Rights of the Child. If access to safe water is reliably assured, it contributes greatly to health --- enabling and encouraging hygiene through key actions such as handwashing, food hygiene, laundry and general household hygiene. When household water security is endangered, contaminated water may transmit disease and lack of water may prevent minimum hygiene behaviors to protect health.

Many of the diseases prevented through use of water in hygiene are the same as those that can be transmitted by water when contaminated.

The most important of these is diarrhea, the second biggest child-killer in the world. Diarrhea is estimated to cause 1.3 million child deaths per year --- about 12 percent of total deaths of children under five in developing countries. Other infectious diseases with similar patterns of transmission include hepatitis A and E, dysentery, cholera and typhoid fever.

Lack of household water security is also associated with skin and eye infections including trachoma, and with schistosomiasis, which may be acquired while collecting water from infested sources.

Many chemicals that have the potential to harm people's health can be found in drinking water. For example an excess of fluoride is associated with crippling skeletal fluorosis. In countries where high levels of arsenic are found in drinking water, the symptoms of arsenicosis are sometimes seen amongst young children.

In 2000, WHO and UNICEF estimated that 1.1 billion people lacked access to an improved water source. Access to an improved water source may be as little as a protected well or spring within an hour's walk of home. But the number of people without access to reliable safe water in or just outside the home is undoubtedly far greater than the number with access to an "improved" source. Around 80 percent of this "unserved" population live in rural areas. Where water must be collected from remote sources --- whether protected or not --- it is often women and children who have this task.

2. Hygiene and sanitation

The safe disposal of human feces --- including those of children --- is a prerequisite to protecting health. In the absence of basic sanitation, a number of major diseases are transmitted through fecal pollution of the household and community environment. These include diarrhoea, schistosomiasis, hepatitis A and E, dysentery, cholera and typhoid fever. Lack of sanitation is also associated with infection with helminth and with trachoma. Trachoma causes irreversible blindness and today about 6 million people are visually impaired by this disease.

Globally, 2.4 billion people, most of them living in peri-urban or rural areas in developing countries, do not have access to any type of improved sanitation facilities. Coverage estimates for 1990 and 2000 show that little progress was made during this period in improving this situation. The lowest levels of facility coverage are found in Asia and Africa where 31 percent and 48 percent of the rural populations, respectively, do not have access to adequate sanitation facilities.

Even if good sanitation facilities are available, they are not always enough to improve people's health. Children and adults must be encouraged to wash their hands with soap or ash before meals and after defecating.

3. Air pollution

Air pollution is a major environment-related health threat to children and a risk factor for both acute and chronic respiratory disease as well as other diseases. Around 2 million children under five die every year from acute respiratory infections. Many are aggravated by environmental hazards.

Indoor air pollution is a major factor associated with acute respiratory infections in both rural and urban areas of developing countries. A pollutant released indoors is often more dangerous to a child's lungs than a pollutant released outdoors. One important concern in developing countries is the exposure to combustion products from biomass fuel and coal, plus reduced ventilation in homes and other places. In the industrialized world, poor indoor environments are characterized by reduced ventilation, high moisture, the presence of biological agents such as molds, and a range of chemicals in furnishing and construction materials.

Outdoor air pollution, mainly from traffic and industrial processes, remains a serious problem in cities throughout the world, particularly in the ever-expanding megacities of developing countries. It is estimated that a quarter of the world's population is exposed to unhealthy concentrations of air pollutants such as particulate matter, sulphur dioxide, and other chemicals.

4. Disease vectors

In principle, all vector-borne diseases are a serious threat to children's health. Some, however, pose a specific threat to children, because a child's immune system is unable to cope with the assault by the infectious agent, or because the way a child behaves may increase vulnerability to disease.

These diseases include:

Malaria, which is transmitted by the mosquito, overwhelmingly kills children. Ninety percent of the burden of malaria is concentrated in sub-Saharan Africa, with over a million deaths a year, mainly of children under five.

Lymphatic Filariasis, an infection of parasitic worms lodging in the lymphatic system can cause the deformations typical of the disease ("lymphedema" and "hydrocoele") in children as young as age 12. The decrease in healthy life caused by this disease is second only in its magnitude to malaria.

Schistosomiasis, a water-based disease caused by bloodflukes (worms that live in the bloodstream), affects children and adolescents. Chronic infection leads to debilitation and degenerative disease. Two hundred million people are infected around the world.
Japanese encephalitis is found in the irrigated rice production systems of South and Southeast Asia. Outbreaks particularly affect children under five (about 90 percent of cases); an average of 40,000 clinical cases are estimated to occur each year, with a mortality rate of 20 percent. Of the survivors, 50 percent will be affected mentally for life.

Leishmaniasis, a parasitic disease transmitted by sandflies, manifests itself either in skin lesions or in damage to internal organs --- the latter form is life threatening with an estimated 59,000 deaths in 2001. Every year an estimated 2 million cases of cutaneous leishmaniasis occur, and an estimated 95 percent of patients are children under five years old.

Dengue fever also affects young children disproportionately in high burden countries. The disease's most lethal form, dengue hemorrhagic fever, kills, on average, over 10,000 children each year. During major outbreaks, children's hospitals can come to a grinding halt as wards are overwhelmed by admissions.

5. Chemical hazards

As a result of the increased production and use of chemicals, a myriad of chemical hazards is nowadays present in children's homes, schools, playgrounds and communities. Chemical pollutants are released into the environment by unregulated industries or are emitted from heavy traffic or toxic waste sites. About 50,000 children, aged 0-14 years old, die every year as a result of unintentional poisoning.

Pesticides unsafely used, stored and disposed of may harm children and their environment. Household cleaners, kerosene, solvents, pharmaceuticals and other chemical products become dangerous if they are kept in inappropriate containers and in places that are accessible to children. Small children are "natural explorers:" they may ingest dangerous chemical products and suffer acute poisoning. The result can be life threatening.

Chronic exposure to various pollutants in the environment is linked to damage to the nervous and immune systems, and to effects on reproductive function and on development. This is because exposure occurs during periods of special susceptibility in the growing child or adolescent. For example, children are very vulnerable to the neurotoxic effects of lead in paint and air, which may reduce their IQ and cause learning disabilities. They are also vulnerable to the developmental effects of mercury released into the environment or present as a food contaminant. Most exposures to toxic chemicals and pollutants are preventable. A number of tools and mechanisms are available to help identify chemical hazards, create safer environments and prevent children's exposure.

6. Unintentional Injuries (Accidents)

Unintentional injuries include road traffic injuries, poisonings, falls, burns and drowning. In 2001, an estimated 685,000 children under the age of 15 were killed by such unintentional injuries. Approximately 20 percent of all deaths from unintentional injuries worldwide occur in children under 15 years old and they are among the ten leading causes of death for this age group. Worldwide, the leading causes of death from unintentional injury among children are road traffic injuries (21 percent of such for this age group) and drowning (19 percent).

Unintentional injuries among children are a global problem, but in certain regions of the world, children and adolescents are disproportionately affected. The vast majority of such unintentional injuries among children occurs in low and middle-income countries. Children in the African, Southeast Asian and Western Pacific regions account for 80 percent of all children's deaths from unintentional injuries.

There are many solutions to these environmental health problems. A range of effective interventions exists in the areas of policy, education, awareness raising, technology development, and behavioral change. Such interventions can be extremely cost-effective and are implemented by policy- and decision-makers, householders, communities, educators, government officials and many other stakeholders. Below we give a few indicative examples of actions that can be taken --- the lists are not exhaustive but illustrate a range of actions that can be considered. Of course, the specific interventions that are implemented in any one setting will depend on the nature and severity of the problem, the local context, the resources available, and the priorities to be addressed.

1. Some examples of effective actions to protect children from risks from water are:

• Extending access to improved sources among the "unserved" in rural and urban areas.

• Targeting hygiene education on key behaviors at both children and adults.

• Safe water storage at home --- and treatment of water in the home when its quality is in doubt --- reduces water contamination and leads to proven health benefits.

• Reliable safe water supply in schools has a direct impact on health and provides a model intervention serving as an educational contribution.

• Protecting all water resources from contamination will contribute to health (that is, not only sources of drinking water but also, for example, water used for bathing and fishing).

• Targeted measures in areas affected by hazardous chemicals in drinking water such as lead, fluoride and arsenic.

2. Some examples of effective actions for improved hygiene and sanitation are:

• Ensure that children have access to safe sanitary facilities and that children's feces are safely disposed of.

• Adequate and separate latrines for boys and girls in schools can encourage latrine use and thus reduce disease transmission.

• Proper waste management and relocation of waste dumps away from human settlements protect children from scavenging and from exposure to hazards.

• Washing hands with soap before meals and after defecating significantly reduces the risk of diarrheal disease.

3. Some examples of effective actions to protect children from air pollution are:

• Good ventilation, clean fuels and improved cooking stoves decrease indoor air pollution and the exacerbation and development of acute respiratory infections.

• Protecting children from smoking and from second-hand tobacco smoke reduces the risk of respiratory disorders and other ill-health effects later in life.

• Use of unleaded gasoline reduces lead exposure in children and prevents developmental disorders.

• Sound transport and health policies reduce respiratory illness and unintentional injuries in urban children.

• Realization of clean air implementation plans reduces the exposure of children to outdoor air pollution.

4. Some examples of effective actions to protect children against vector-borne diseases are:

• As children usually go to bed earlier than adults, at the time mosquitoes become active, the use of insecticide-treated mosquito nets and the screening of windows, doors and eaves provide a very effective means of protecting them against malaria.

• General environmental management, including improved water management in irrigated areas, placing cattle strategically between breeding places and homesteads, and drainage or filling of water collections, may help reduce transmission risks.

• Combined irrigated rice production and pig rearing close to housing must be avoided in South and Southeast Asia to break the Japanese encephalitis cycle.

• Hygiene education and designated safe places to swim (kept snail-free through regular mollusciciding, an application upstream of a chemical which eliminates snails), as well as other environmentally sound measures and periodic deworming, will reduce the transmission risks of schistosomiasis and help control morbidity.

• Cover water storage containers, and periodically empty and dry out various containers that retain water to eliminate potential mosquito breeding sites including buckets, discarded food containers, drums, flower vases, and car tyres (where water can collect). This will help bring down dengue transmission risks.

5. Some examples of effective actions to protect against chemical hazards are:

• Ensure safe storage and packaging, and clear labeling, of cleaners, fuels, solvents, pesticides and other chemicals used at home and in schools.

• Promote the use of child-resistant packages for pharmaceuticals and for chemical products.

• Inform parents, teachers and childcare providers about the potential chemical hazards in the places where children spend their time.

• Train healthcare providers on the recognition, prevention and management of toxic exposures, and on the use of the pediatric environmental history to investigate specific risks to which children are exposed.

• Incorporate the teaching of chemical safety and health into school curricula.

• Create and enforce legislation to promote the safe use and disposal of chemicals.

• Promote policies to reduce and remedy environmental pollution.

• Avoid the construction of homes, schools and playgrounds near polluted areas and hazardous installations.

• Promote poison-control educational campaigns.

6. Some examples of effective actions to protect against unintentional injuries (accidents):

• Develop national policies on injury prevention and advocate for greater resources.

• Improved enforcement of existing laws.

• Institute systematic surveillance for unintentional injuries.

• Educate community members in first aid.

• Coordinate emergency services.

• Install window guards and bed rails in the home.

• Use helmets when riding on motorcycles, scooters and bicycles.

• Use child safety seats and safety belts in motor vehicles.

• Raise or enclose cooking areas.

Teach children to swim and encourage supervision of children around water.

• Use fire-resistant fabrics.

• Use child-proof caps for containers of pesticides, medicines and kerosene.

• Develop, where possible, public awareness campaigns to teach injury prevention.

(April 7 is World Health Day, which this year revolves around the theme of creating healthy environments for children.)

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